Perspective review on Municipal Solid Waste-to-energy route: Characteristics, management strategy, and role in circular economy

The proper handling of Municipal Solid Waste (MSW) is critical due to its high generation rate and the potential to minimise environmental impacts by simultaneously reducing resource depletion and pollution. MSW utilization for recycling is important for transforming the linear economy model into a circular one. The current review analyses and categorises MSW to energy technologies into direct and indirect approaches taking the Circular Economy perspective. The direct approach involves incinerating MSW for heat recovery. The indirect approach, including thermochemical and biochemical processes, is more complicated but attractive due to the variety of the valorized products - such as syngas, bio-oil, biochar, digestate, humus. However, consensus on the best MSW treatment approach is yet to be established due to the inconsistency of assessment criteria in the existing studies. In the case of converting MSW to energy (Waste-to-Energy - W2E), its economic indicators, such as capital, compliance, and operation cost, are important criteria when implementations are considered. In the current work, the critical characteristics of technologies for the MSW to energy routes are scrutinised. In addition, the economic characteristics and the role of MSW in the circular bio-economy is also thoroughly evaluated. Methods to advocate the industrial adoption and important assessing aspects of W2E are proposed at the end of the review to address the environmental and resource management issues related to MSW - most notably dealing with the uncertainty in composition and amounts, the energy efficiency and the resource demands of the W2E processing.

Automated summary

The proper handling of Municipal Solid Waste (MSW) is crucial for minimizing environmental impacts and transforming the linear economy model into a circular one. This review analyzes and categorizes MSW to energy technologies from a Circular Economy perspective. The direct approach involves incineration for heat recovery while the indirect approach includes thermochemical and biochemical processes, which produce a variety of valuable products. However, there is no consensus on the best MSW treatment approach due to inconsistent assessment criteria. This study scrutinizes the critical characteristics of MSW to energy technologies and evaluates their economic aspects and role in the circular bio-economy.